1. Field of the Invention
This invention relates to a multiprocessor and its control mechanism in which a data set is sequentially renewed by a series of data having snap shots (instantaneous values) of the data set at arbitrary points of time are assigned at a high speed to element processors of the multiprocessor, so that instructions for the snap shots such as drawing instruction primitives are efficiently executed in parallel.
2. Description of Related Art
PHIGS (Programmer's Hierarchical Interactive Graphics System), which is one of existing three-dimensional graphics interfaces, holds data in the form of a structure, estimates the data structure upon drawing, and generates a series of drawing instructions. The series of drawing instructions includes attribute setting instructions and drawing instructions (primitives). The attribute setting instructions enter their attribute values in corresponding items in TSL (Traversal State List). The primitives perform drawing by using attribute values held in TSL when the primitives are issued. When parallel execution of this by the multiprocessor is desired, it is efficient to assign processors to respective primitives and have them execute the primitives. In this case, each processor to which the primitives are assigned must remember the contents of TSL at the time of assignment of the primitive. To this end, each processor must copy TSL in its own region before processing the primitives. The size of TSL is normally more than 1000 bytes. Therefore, overhead increases because of an increase in the traffic of the bus and so on, and the advantage of the high speed nature by parallel execution of the multiprocessor is decreased.
Japanese Patent Publication 4-213736 discloses a technique for logging changes in a memory of an active processor of a fault tolerant computer occurring on and after a check point and for modifying memory of a backup processor upon the start-up thereof. This application, however, does not teach the use of multiple memories in a single processor to hold both a data set during execution and a current data set.